Electromagnetic actuating mechanism.



H. M. STEVENS.

ELECTROMAGNETIC AGTUATING MECHANISM.

APPLICATION FILED AUG.4,1913.

Patented Dec. 1, 1914.

6 v I n e w W m o 4 u n m ,u 2 I .7. e A 2 "M 0% .m 5 5 5 05 I i m M H a w 11%; W 5 5 F 5 a y do b 2 9 Z 1 M5 fir X T 7 n ".111 2 W4 1 6 8 w 3 5 2 2 9 7 U w my; I I w 4 0 E 3 v w v 3 0 5 v. ,1 7 9 Z l 2 ill.-- 1 1 2 u .1 a0 w m Iiiwiii 11%]; mo 9 1 11.1 V... bl u S n u w 2 u r s 8 5 e m 1 t m 2 1 I. I W 0 a arias-rare FFICE.

HARRY M. STEVENS, 01" SCHENEGTADY, NEW YORK, ASSIGNOR T0 GENERAL ELECTRIC- COMPANY, A CQRPORATZQN 6F NEW YORK.

nnnornoiuaennrro estuarine rarcnnnrsm.

Specification. of Letters Patent.

Patented Dec.- 1, 1914;

Application filed August 4, 1913. Serial Ho. 782,795.

To all whom it may concern:

Be it known that I, HARRY M. Srnvnns, a citizen of the United States, residing at Schenectady, couhty of. Schenectady, State of New York, have invented certain new and useful Improvements in Electromagnetic Actuating Mechanism, of which the following is a specification.

My invention has reference to mechanism comprising an electromagnet, such as a solenoid of the iron clad lunger type, the armature or core of which in its movement toward the magnet performs a useful operation, such as the closing of a' switch. It is,

of course, desirable to maintain the circuit of the magnet closed until this movement is completed, as otherwise the switch will not be completely closed.

The object of my invention is to provlde means for maintainin the circuit ofthe magnet closed until t e movement of its armature or core is completed and for then opening its circuit in order to avoid waste of energy and to prevent injury to the magnet.

For a fuller understanding of my in vention, reference may be had to the accompanyin drawings, in which, merely for purposes of illustration, '1 have shown one of the various forms in which my invention may be embodied, and in which- Figure l is a vertical section through the magnet showing the cooperating parts in the position which they occupy just before the core of the magnet is attracted; Fig. 2 is a side elevation of the same showing the position which the parts occupy just after the core of the magnet has completed its movement, but before the circuit of the magnet has'been opened, and Fig. 3 is a detail view showing the positions of the auxiliary armature and cooperating parts after the armature has been attracted and has opened the circuit of the magnet, and after the core of the magnet has dropped back to its initial unattracted position. v

In the particular form of device shown in the drawings, 1 is the coil for the magnet, which is surrounded by an iron shell 2 closed at the upper end but provided with a screwthreaded opening 3 in which is received the screw-threaded contracted part 4 of a block 4, the lower and larger end 4. of which constitutes a stationary iron core for the magnet. The core 4* cooperates with a movable core or armature 7, passing through the base plate 5, which coreengages'a plunger 8 passing axially through the block 4. The upper end of this plunger is provided with a head 9 which engages a roller 10 on one endof a lever 11 which is pivoted at 12 on a bracket 13. The opposite end of the lever llmay be connected to a switch so as to close the same when the end of the lever which is engaged by the plunger 8 is lifted, or the movement of the lever may perform any other useful function.

In order to maintain the circuit of the magnet closed until its core has completed its movement, the circuit of the magnet comprising the conductor 14 is controlled by a pair of contacts 15 and 16, carried by a: block 17 which is mounted on a spring strip 18.- This spring strip may be secured to a bracket which is in turn secured to the base plate 5. An auxiliary armature 29 is provided for the magnet, which is pivoted at its lower end at 21 and is curved outwardly at 22 at its upper end. This armature is normally heldaway from the magnet by a spring 24-, one end of which is attached to a bracket 25, while its other end is connected to an arm 26 on the armature 20. The armature is provided with a contact plate 27 which bridges the contacts 15 and- 16 when the armature is in its outer or rewhen the core 7 has been attracted and brought into engagement with the block 4, a metallic path for the magnetic circuit is then completed and the shell, or some part of it, which forms a constricted portion of the magnetic circuit, becomes saturated. The saturation of this part of the shell of the magnet causes the creation of a stray field suflicient to result in the attraction of the auxiliary armature 20 to the shell of the magnet, whereupon the circuit of the magnet is opened at thecontacts 15 and 16. In order that the circuit of the magnet may remain open when the auxiliary armature" is attracted, a liLtCllrOl' lock is provided, comprising a lever 28 which is pivoted at 29 on a bracket 30 projecting upwardly from the shell of the magnet. The outer end of one arm of the lever 28 is engaged by a pin 31 carried by the 'lever 11. The other end-of the' lever 28, comprises an arm 32 formed w tha shoulder to constitute a latch. The arm also comprises'a finger 33 which -engages a stop 3-1 on the bracket .30; The

lateh'.32 is drawn downwardly by a spring 35, one end of which is connected to the latch 3:2, while the other end is connected to the stop 31, the movement of the'latch being limited by the engagement of the finger 33- *with the stop 3t. W hen the lever 28 is held -in the position indicated in Fig. 1 by the pin\31, the latch 32 is not in a position to en- 9 gage the upper end of the auxiliary armaturelQ O, so that in case the armature is llfted by accident it at once resumes its original position. As soon, however, as the lever 11. has been lifted by the movement of the core 7 and the lever 28 is thus tree to occupy the position indicated in vlei'g. 2, the latch 32 is lowered by the spring so that it is in a ating parts is as follows: \Vhen the magnet is energized in the usual manner, its core 7 is attracted and brought into engagement with the block 1. at which time the metallic path of the. n'lagnetic circuit is .completed.

- Shortly after this operation takes place, the

shell of the. imignet becomes saturated and the stray lield which is thus created is sufii t-ient'to attract the armature Q0. The armatin-e on being attracted breaks the circuit through the coil 1 at the contacts 15 and 16 thereby del nergizing thecoil and allowing the core T to tail to normal position. This operation, however, takes place an appreciable time after the core of the magnet has completed its movement and after the oil switch or other device. which is operated in response to the movement of the core of the armature, has been actuated.

l have reterred, tor convenience, in certain of the claims to an iron clad magnet,

' the drawing.

but it is not necessary for the purposes of my invention that a magnetic shell should completely surround the coil, as shown in When I refer to an'iron clad magnet, I mean any form of magnet having amagnetic circuit through a metallic path outside the. magnet winding.

In accordance with the provisions of the patent'statutes, I have described the principle of operation of my invention, together with the apparatus which I now consider to represent the best embodiment thereof; but I desire to have it understood that the apparatus shown is only illustrative, and that the invention can be carried out by other means.

What 1 claim as new and desire to secureby Letters Patent of the United States, is v 1. In. combination, an iron clad magnet, the armature of which, when attracted, completes a metallic path for the magnetic cirwit and the shell of which becomes saturated on the completion of said metallic path, and an auxiliary armature for said magnet which normally closes the circuit of said magnet and is attracted and opens the circuit of said magnetonlyin responseto the stray field created by said magnet when the principal armature is attracted, and

means for locking said auxiliary'armature' in circuit opening position.

2. In combination, an iron clad plunger magnet, the core of which, when attracted, completes the magnetic circuit, and the shell of which becomes saturated when the core has been attracted and the metallic path thus completed, an auxiliary armature for said magnet which isatt-racted only in response to the stray magnetic field which is created when the shell of the magnet is saturated,-

me-ans controlled by said auxiliary armature for closing the circuit of said magnet when the armature is in its normal position and for opening the circuit of the same when the armature is attracted, a -member which is moved in response to the movement of the coil. and a locking member for said armature which is disabled by saidmovable member when the latter is in its normal position.

3. An operating mechanism for an electric switch comprising an electromagnet having a magnetic circuit saturated at a predeter mined point when substantially closed, a main armature movable in response to the energization of the magnet to substantially close said magnetic circuit, an auxiliary arcopies ofthie patent may be obtained for flve cents each, by addressing the "Commissioner of Patents,

1 Washington, D. O. 

